Instruments and methods for use in performing knee surgery

ABSTRACT

A system and method for aligning a patient&#39;s leg, for establishing the ultimate alignment of the leg prior to making a horizontal femoral cut or a horizontal tibial cut, for preparing the distal femur for receiving a femoral implant, and for making the horizontal, femoral and tibial cuts. The system and method incorporate a spacer, a cutting guide, and a template. The spacer is insertable between a distal femur and a proximal tibia to rotate the tibia with respect to the femur into the desired alignment. The cutting guide is engageable with the spacer, and can be fixed to the proximal tibia and the distal femur. The cutting guide has openings sized and shaped to guide a surgical saw to make the horizontal femoral cut and the horizontal tibial cut. The template is shaped to closely conform with the distal femur to allow the leg to be extended and to allow the procedure to be performed without dislocating a patella. Through one method of the present invention, the practitioner can select the desired ultimate alignment of the leg prior to making the horizontal, tibial and femoral cuts. As a result, when a replacement knee is implanted, the leg will be in the desired alignment.

TECHNICAL FIELD

[0001] The invention relates to surgical apparatus and methods. Moreparticularly, the invention relates to instruments and methods for useduring knee replacement procedures.

BACKGROUND OF THE INVENTION

[0002] Traditionally, when performing a partial knee replacementprocedure, a practitioner first makes a horizontal femoral cut in thedistal femur to remove diseased bone and provide a surface for receivinga femoral prosthesis. The proximal tibia is then cut to remove anydiseased bone and provide a surface and sufficient clearance forreceiving a tibial prosthesis. The femoral and tibial prostheses mate toform a replacement partial knee.

[0003] In this traditional procedure, the ultimate alignment of the legafter the prostheses are implanted is determined by the location of thetibial cut with respect to the femoral cut. After the femoral cut hasbeen completed, the practitioner selects the location for the tibial cutbased primarily on experience and with the understanding that tibialprostheses are available in a limited number of thicknesses. The tibialcut accordingly is made as close to the proximal end of the tibia aspossible, based on how much of the tibia must be removed due to disease,plus whatever additional spacing is required to accommodate the closeststandard sized tibial prosthesis. After the tibial cut is made, theprostheses are temporarily implanted and the alignment of the leg isanalyzed. To adjust the leg alignment, the practitioner can replace thetibial prosthesis with one of a different thickness, can remove morebone, or can do both. This procedure is followed until the leg is in thedesired alignment and balance.

[0004] Because the location of the tibial cut is independent of thelocation of the femoral cut, such a procedure may result in thepractitioner making numerous cuts before the desired leg alignment andtension are attained. Also, as a result of this trial-and-error process,practitioners may at times remove more bone than necessary.

[0005] One method and instrumentation for making horizontal, femoral andtibial cuts is disclosed in U.S. Pat. Nos. 5,122,144 and 5,234,433, bothto Bert et al. The Bert et al. patents disclose a first instrument foraligning and making the horizontal femoral cut, and a second instrumentfor aligning and making the horizontal tibial cut.

SUMMARY OF THE INVENTION

[0006] The present invention relates to instrumentation and methods foruse during a knee replacement procedure. In one embodiment of theinvention, the instrumentation includes first and second membersconfigured to contact the distal femur and proximal tibia, respectively;an actuator linked to the first and second members; and a cutting guide.The first member is designed to contact either the medial or lateralside of the distal femur and to exert a force on the distal femur in aproximal direction. The second member is designed to contact thecorresponding side of the proximal tibia, and to exert a force on theproximal tibia in a distal direction. The second member is movable withrespect to the first member to allow a practitioner to rotate the tibiawith respect to the femur in the horizontal plane. The actuator iscontrollable to move the second member, and to retain the second memberin a desired position with respect to the first member. Accordingly, theactuator can be manipulated to rotate the tibia with respect to thefemur (adjusting the tibiofemoral alignment), and to retain the leg inthe desired alignment. The cutting guide is designed to be temporarilyfixed to the proximal tibia and the distal femur. The cutting guide hasopenings therethrough that are sized and shaped to guide a surgical sawfor making the horizontal, tibial and femoral cuts.

[0007] The system of this embodiment allows the practitioner to positionthe leg in the alignment that is desired at the end of the implantprocedure, and to cut both the femur and the tibia while the leg isfixed in this alignment so that preselected prostheses can be implantedin the knee and the knee will have the desired alignment after theprostheses have been implanted. The distal femoral and proximal tibialcuts can be parallel to each other and perpendicular to the tibialweight-bearing axis. The system may also allow the practitioner toperform the procedure using a smaller incision than that traditionallyused, and to avoid excessive bone removal.

[0008] In another embodiment of the present invention, theinstrumentation has a spacer used in place of the first and secondmembers discussed above. In this particular embodiment, the practitionerhas a number of potential spacers available for use, each spacer havinga distal end with a distinct thickness. The practitioner can select thedesired spacer that creates the preferred leg alignment, then can makethe femoral and tibial cuts as described above. As with the previousembodiment, this embodiment allows the practitioner to set the ultimatealignment of the leg prior to making the bone cuts, and to createparallel cuts which are perpendicular to the floor and which avoidexcessive bone removal.

[0009] In another embodiment, the instrumentation of the presentinvention incorporates a cutting and drilling guide for use in preparingthe distal femur to receive a femoral prosthesis. The cutting anddrilling guide has a bottom surface that is shaped to conform with thedistal femur after the horizontal femoral cut has been made. The guidehas a posterior portion that engages the posterior distal femur, and ananterior portion that mates with the anterior distal femur. The proximalportion is contoured to closely conform with the posterior distal femurto allow the practitioner to flex the leg during the procedure toconfirm the guide's alignment. The anterior portion of the guide has alaterally tapered thickness that complements the patella. The guideaccordingly can be used without the practitioner first dislocating thepateila.

[0010] Embodiments of the present invention are also directed to methodsfor aligning the leg prior to performing knee surgery, methods foraligning the horizontal femoral and tibial cuts, and methods for makingboth the horizontal tibial and the horizontal femoral cuts using asingle guide to create the parallel cuts and the desired, ultimatealignment in the leg. The present invention is also directed towardvarious combinations of the above instrumentation and methods, as wellas the instrumentation and methods used in connection with other suchinstruments and used in performing other such methods.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 is an isometric view of an alignment device according toone embodiment of the present invention.

[0012]FIG. 2 is an exploded view of the alignment device of FIG. 1.

[0013]FIG. 3 is a top plan view of the alignment device of FIG. 1.

[0014]FIG. 4 is a side elevation view of the alignment device of FIG. 1.

[0015]FIG. 5 is a side elevation view of a first member of the alignmentdevice of FIG. 1.

[0016]FIG. 6 is a top plan view of the first member of FIG. 5.

[0017]FIG. 7 is a side elevation view of a second member of thealignment device of FIG. 1.

[0018]FIG. 8 is a top plan view of the second member of FIG. 7.

[0019]FIG. 9 is an end view of the alignment element of FIG. 1 shown ina first position.

[0020]FIG. 10 is an end view of the alignment device of FIG. 1 shown ina second position.

[0021]FIG. 11 is a top plan view of an alignment device according toanother embodiment of the present invention.

[0022]FIG. 12 is a side elevation view of the alignment device of FIG.11.

[0023]FIG. 13 is an end view of the alignment device of FIG. 11.

[0024]FIG. 14 is an end view of a variation of the alignment deviceshown in FIG. 13.

[0025]FIG. 15 is an end view of another variation of the alignmentdevice shown in FIG. 13.

[0026]FIG. 16 is an isometric view of a cutting guide according to oneembodiment of the present invention.

[0027]FIG. 17 is a top plan view of the cutting guide of FIG. 16.

[0028]FIG. 18 is a sectional side elevation view of the cutting guide ofFIG. 17, viewed along Section 18-18.

[0029]FIG. 19 is an isometric view of a combination of an alignmentdevice and a cutting guide according to one embodiment of the presentinvention.

[0030]FIG. 20 is an exploded isometric view of another cutting guide anda portion of another alignment device according to another embodiment ofthe present invention.

[0031]FIG. 21 is a top plan view of a femoral cutting and drilling guideaccording to one embodiment of the present invention.

[0032]FIG. 22 is a side elevation view of the guide of FIG. 21.

[0033]FIG. 23 is an end view of the guide of FIG. 21.

[0034]FIG. 24 is a sectional end view of the guide of FIG. 21, viewedalong Section 24-24.

[0035]FIG. 25 is a top plan view of a femoral implant according to oneembodiment of the present invention.

[0036]FIG. 26 is a side elevation view of the femoral implant of FIG.25.

[0037]FIG. 27 is an isometric view of a mounting instrument according toone embodiment of the present invention.

[0038]FIG. 28 is a plan view of a driving member from the mountinginstrument of FIG. 27.

[0039]FIG. 29 is all exploded plan view of a bearing and a circlip fromthe mounting instrument of FIG. 27.

[0040]FIG. 30 is an exploded plan view of a handle and set screw fromthe mounting instrument of FIG. 27.

[0041]FIG. 31 is a plan view of a pin driver according to one embodimentof the present invention.

[0042]FIG. 32 is an end view of the pin driver of FIG. 31.

[0043]FIG. 33 is a plan view of a nut driver according to one embodimentof the present invention.

[0044]FIG. 34 is an end view of the nut driver of FIG. 33.

[0045]FIG. 35 is a schematic isometric view of a knee—minus thepatella—prior to the procedure of the present invention.

[0046]FIG. 36 is a schematic isometric view of the knee of FIG. 35 aftera preliminary tibial cut has been made.

[0047]FIG. 37 is a front elevation view of the knee of FIG. 36 after analignment device according to one embodiment of the present inventionhas been inserted between the femur and the tibia.

[0048]FIG. 38 is a front elevation view of the knee of FIG. 37 after thealignment device has been manipulated, and an alignment rod according toone embodiment of the present invention.

[0049]FIG. 39 is a front elevation view of the knee of FIG. 38 after acutting guide according to one embodiment of the present invention hasbeen mounted to the alignment device.

[0050]FIG. 40 is a side elevation view of the knee, alignment device andcutting guide of FIG. 39.

[0051]FIG. 41 is a front elevation view of a knee and first spaceraccording to another embodiment of the present invention.

[0052]FIG. 42 is a front elevation view of the knee of FIG. 41 in whichthe first spacer has been replaced by a second spacer, and anothercutting guide according to another embodiment of the present invention.

[0053]FIG. 43 is an isometric view of a combined alignment device andcutting guide according to still another embodiment of the presentinvention.

[0054]FIG. 44 is an exploded isometric view of the combined alignmentdevice and cutting guide of FIG. 43.

[0055]FIG. 45 is a side elevation view of the combined alignment deviceand cutting guide of FIG. 43, in a first position.

[0056]FIG. 46 is a side elevation view of the combined alignment deviceand cutting guide of FIG. 43, in a second position.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

[0057] The present invention is generally directed toward instrumentsfor use during knee replacement procedures, and toward methods of usingthe same. Several embodiments of the invention may allow a medicalpractitioner to perform a complete unicompartmental knee replacementthrough a relatively small incision with reduced trauma to the bone andsoft tissues, and accordingly may reduce the morbidity, pain andrecuperation time to the patient, as well as reducing complicationsassociated with intramedullary guide placement. Embodiments of thepresent invention may also allow the practitioner to accuratelydetermine the ultimate alignment of the leg prior to making thehorizontal, femoral and tibial cuts, and thus may reduce problems orinefficiencies related with the trial-and-error method of the prior art.Embodiments of the invention may also allow the practitioner to makeboth the horizontal, femoral and tibial cuts using a single cuttingguide, and to prepare the distal femur for receiving the implant withoutdislocating the patella. Many specific details of certain embodiments ofthe invention are set forth in the following description and in FIGS.1-46 to provide a thorough understanding of such embodiments. Oneskilled in the art, however, will understand that the present inventionmay have additional embodiments, or may be practiced without several ofthe details described in the following description.

[0058] FIGS. 1-4 illustrate an alignment device 100 according to onepossible embodiment of the invention, generally incorporating a firstmember 102 and a second member 104. In the orientation illustrated inFIG. 1, the first member 102 is positioned below the second member 104.The first member 102 has a central body 106, a prong 108 projecting in adistal direction from the central body, and a post 110 projecting in aproximal direction from the central body. The prong 108 is elongated andis offset from the central body 106 of the first member 102 such thatthe prong is generally aligned with the second member 104.

[0059] The post 110 projects from the central body 106 of the firstmember 102 in a proximal direction that is essentially opposite thedirection in which the prong 108 projects. As discussed below, thelength and shape of the post 110 is selected to engage with othersurgical implements for use in performing the methods of the presentinvention.

[0060] The second member 104 of the illustrated embodiment is agenerally U-shaped, flat member having two opposing legs 112 and a base114 extending between the two legs. The base 114 of the second member104 is generally aligned with and positioned above the central body 106of the first member 102. Due to the offset of the prong 108 with respectto the central body 106 of the first member 102, the legs 112 of thesecond member 104 generally lie in a common plane with the prong. Thesecond member 104 is movable with respect to the first member 102 tocause the legs 112 to move out of this common plane.

[0061] Although the alignment device 100 is illustrated with a singleprong 108 and a pair of opposing legs 112, it is understood that thefirst member 102 can have two or more prongs 108, that the second member104 can have more or a single leg 112, and that the device can have avariety of shapes suitable for performing the methods described below.

[0062]FIGS. 5 and 6 further illustrate the first member 102 according tothis particular embodiment of the invention. The central body 106 of theillustrated embodiment is integrally formed with the post 110 and theprong 108. The central body 106 projects laterally in opposingdirections with respect to the length of the prong 108 and the post 110(FIG. 6). A rod 116 projects from each of the opposing sides of thecentral body 106 in an upward direction as illustrated in FIGS. 1 and 5.The rods 116 are substantially smooth, and project approximately ½ inchabove the surface of the central body 106. The rods 116 are designed toguide the second member 104 as it moves during operation. It isunderstood that the rods 116 can take a variety of shapes and sizes, anyof which is suitable for this particular function. For example, the rods116 can have rectilinear or oval cross-sectional shapes.

[0063] The prong 108 in the illustrated embodiment is a generallyelongated, flat member sized and shaped to be inserted between thedistal femur and the proximal tibia. The illustrated prong 108 has arectangular cross-section with a generally flat upper surface 118 and agenerally flat lower surface 120. The illustrated prong 108 isconsiderably wider than it is tall to provide the prong with sufficientsurface area and strength for separating the tibia from the femur.Depending on the material used, however, the thickness andcross-sectional shape of the prong can vary. For example, the prong canhave a circular, oval, or square cross-section, or can have a taperedtip to facilitate insertion between the distal femur and proximal tibia.

[0064] The post 110 in the illustrated embodiment has a circularcross-section having a diameter of approximately ¼ inch. The size andshape of the post 110 is selected to engage with other instrumentsdiscussed below. Accordingly, the sizes and shapes of each of theseelements can be varied as necessary and suitable for performing theirdescribed functions. The post 110 can similarly be removable from thefirst member 102 and can be positioned at any location along the centralbody 106. For example, the post 110 can project from one lateral edge ofthe central body 106.

[0065]FIGS. 7 and 8 further illustrate the second member 104 accordingto this particular embodiment of the invention. The base 114 of thesecond member 104 has a threaded hole 122 (FIG. 8) extending through itsentire thickness for engagement with a screw 124 (FIG. 2) or similarthreaded member. At opposing ends of the base 114, an aperture 126having a smooth internal sidewall extends through the second member 104.A sleeve is aligned with that of the aperture 126. The sleeve 128 has asmooth internal sidewall complementary with that of the aperture 126.The apertures 126 and sleeves 128 are aligned to mate with the rods 116(FIG. 6) on the first member 102. The apertures 126 closely mate withthe rods 116 to prevent the second member 104 from rotating over asubstantial angle with respect to the first member 102. Although thethreaded hole 122 is shown centrally located and the apertures 126laterally located, it is envisioned that the aperture can be centrallylocated, and that the threaded hole can be located on one or both of thelateral portions of the central body 106.

[0066] The legs 112 on the second member 104 are elongated and have agenerally rectangular cross-section similar to that of the prong 108 ofthe first member 102 (FIG. 2). The legs 112 have a top surface 130 and abottom surface 132. The top and bottom surfaces 130/132 are generallyflat and smooth, and are generally aligned to be coplanar with the upperand lower surfaces 118/120 of the prong 108 when the first and secondmembers 102/104 are fully engaged with each other (see FIG. 4). The legs112 in the illustrated embodiment are shorter than the prong 108 (seeFIG. 3). The relative length of the prong 108 and the legs 112 can vary,however, based on the practitioner's needs or other factors.

[0067]FIG. 9 illustrates the alignment device 100 configured forinsertion between the distal femur and proximal tibia. The screw 124 hasbeen withdrawn from the base 114 by a sufficient distance to allow thebase to contact the central body 106. As a result, the prong 108 isgenerally aligned with the legs 112. The thickness between the lowersurface 120 of the prong 108 and the top surfaces 130 of the legs 112 isa minimum thickness “t” in this configuration. This minimum thickness“t” enables the distal end of the alignment device 100 to be slidablyinserted between the distal femur and the proximal tibia.

[0068]FIG. 10 illustrates the alignment device 100 configured to spacethe proximal tibia from the distal femur. In this configuration, thescrew 124 has been threaded through the base 114 to space the base apartfrom the central body 106. As a result, the lower surface 120 of theprong 108 is spaced apart from the top surfaces 130 of the legs 112 byan increased thickness “T.” As the screw 124 is threaded into the base114, the increased thickness “T” further increases to further space thetibia apart from the femur.

[0069] Embodiments of the alignment device 100 may have many advantagesover instruments of the prior art. For example, the alignment device 100may allow a practitioner to rotate a patient's tibia in the horizontalplane relative to the femur to position the leg in the desired alignmentprior to making the bone cuts necessary for implanting prostheses. As aresult, the practitioner may be better able to create the desiredultimate alignment in the patient's leg after implant. In addition, thepractitioner may be able to perform the procedure making fewer cuts and,consequently, remove the least amount of bone necessary.

[0070] FIGS. 11-13 illustrate a spacer 140 according to anotherembodiment of the present invention. The spacer has a distal portion 142and a proximal portion 144. The distal portion 142 has a rectilinearcross-section and is substantially wider than it is thick to allow thespacer to be inserted between the distal femur and the proximal tibia.The distal portion has a thickness “d1” (FIG. 13). The proximal portion144 of the spacer 140 has a size and shape similar to the post 110described in the above embodiment.

[0071]FIGS. 14 and 15 show other variations of spacers 140 a/140 b,respectively. The spacer 140 a is generally sized and shaped similar tospacer 140 described above. A distal end 142 a of spacer 140 a, however,has an increased thickness “d2” (FIG. 14) that is slightly larger thanthickness “d1” of the previous spacer. Similarly, a distal end 142 b ofspacer 140 b has a further increased thickness “d3” (FIG. 15) that islarger than increased thickness “d2.”

[0072] Embodiments of the spacers 140/140 a/ 140 b have a number ofadvantages over the prior art. For example, a practitioner can insertone of a number of spacers between a patient's distal femur and proximaltibia to create the desired alignment in the patient's leg prior tomaking any bone cuts necessary for implanting prostheses.

[0073] FIGS. 16-18 illustrate a cutting guide 150 according to oneparticular embodiment of the present invention. The cutting guide 150has a generally block-shaped body with a tibial end 152 and an opposingfemoral end 154. The tibial end 152 of the cutting guide 150 terminatesin a generally flat surface with rounded corners. Three tibial pinguides 156 are distributed along the tibial end 152 of the cutting guide150. Each of the tibial pin guides 156 extends through the cutting guide150, and is sized to closely receive a standard surgical pin for fixingthe cutting guide to the proximal end of the tibia.

[0074] The femoral end 154 of the cutting guide 150 terminates in agenerally triangular end portion with a rounded apex. A single femoralpin guide 158 is located near the femoral end 154 of the cutting guide150. Similar to the tibial pin guides 156, the femoral pin guide 158extends through the cutting guide 150, and is shaped to receive asurgical pin for fixing the cutting guide to the femur. It is understoodthat the number and arrangement of the tibial pin guides 156 and femoralpin guides 158, as well as the general shapes of the tibial end 152 andfemoral end 154 of the cutting guide 150, can vary significantly withoutaffecting the function of the cutting guide 150. For example, thecutting guide 150 can have a rectilinear or oval overall shape, and moreor fewer pins can be used for particular procedures or particularpractitioners, as desired or as otherwise required. Similarly, the sizeor shape of the tibial pin guides 156 and/or femoral pin guides 158 canbe modified to receive screws or other fasteners.

[0075] A mounting opening 160 is centrally located on the cutting guide150. The mounting opening 160 has a circular cross-sectional shape andextends through the entire thickness of the cutting guide 150. Themounting opening 160 is slightly larger than the post 110 projectingfrom the central body 106 of the first member 102 (FIG. 1). Accordingly,the cutting guide 150 can be mounted on the post 110, as illustrated inFIG. 19. The cutting guide 150 can be rotated about the post 110 toallow the practitioner to change the alignment of the cutting guide withrespect to the patient's leg, as desired.

[0076] A first tibial cutting groove 164 and a second tibial cuttinggroove 166 are positioned between the mounting opening 160 and thetibial end 152 of the cutting guide 150. As best illustrated in FIG. 18,the first and second tibial cutting grooves 164/166 extend through thecutting guide 150 at approximately a 7 degree angle of declination(angles “α” and “β”). The tibial cutting grooves 164/166 aresufficiently wide and tall to receive a surgical cutting saw, and todirect the saw into the proximal tibia for making what is generallyreferred to as the horizontal tibial cut. It is envisioned that thetibial cutting grooves 164/166 can be oriented at different angles withrespect to the cutting guide 150. For example, the tibial cuttinggrooves 164/166 can be perpendicular to the length of the cutting guide150, or can be at a lesser or greater angle than the illustrated 7degrees.

[0077] A femoral cutting groove 162 is located between the mountingopening 160 and the femoral end 154 of the cutting guide 150. Thefemoral cutting groove 162 is generally sized and shaped the same as thetibial cutting grooves 164/166 to receive the saw. The femoral cuttinggroove 162, however, is oriented perpendicular to the length of thecutting guide 150. The femoral cutting groove 162 is oriented to guidethe saw to make what is generally known as the horizontal femoral cut.As with the tibial cutting grooves 164/166, the femoral cutting groove162 can be angled with respect to the cutting guide 150.

[0078] As best illustrated in FIG. 17, the femoral cutting groove 162 islocated to position the horizontal femoral cut approximately 3.5millimeters from the centerline of the mounting opening 160 (distance“A”). As illustrated in FIGS. 9 and 10, the centerline of the post 110,which is colinear with the centerline of the mounting opening, isaligned with the lower surface 120 of the prong 108. Consequently, whenthe alignment device 100 is inserted between the distal femur and theproximal tibia with the lower surface 120 in contact with the distalfemur, the centerline of the mounting opening 160 is aligned with thedistal end of the femur. A cut made using the femoral cutting groove 162will accordingly remove approximately 3.5 millimeters of bone from thedistal end of the femur. This thickness is selected due to the currentlystandard thickness of a femoral prosthesis. The distance “A” between themounting opening 160 and the femoral cutting groove 162 can vary toaccommodate different implants.

[0079] Returning to FIG. 17, the first tibial cutting groove 164 islocated to position the horizontal tibial cut eight millimeters from thedistal end of the femur (distance “B”), and the second tibial cuttinggroove 166 is located to position the horizontal tibial cut tenmillimeters from the distal end of the femur (distance “C”). These twodimensions are consistent with two currently standard thicknesses oftibial plates used in tibial prostheses. The “B” and “C” distances canvary, however, as necessary to accommodate particular prostheses or theparticular needs or desires of the practitioner. For example, the firstand second tibial cutting guides can be 12 and 14 millimeters from thedistal end of the femur, or can include various combinations of thesedistances.

[0080]FIG. 19 illustrates one possible combination of the alignmentdevice 100 and the cutting guide 150 of the present invention. Whenconfigured for a procedure, the femoral end 154 of the cutting guide 150is positioned on the side of the first member 102 of the alignmentdevice 100 and the tibial end 152 of the cutting guide 150 is positionedon the side of the second member 104 of the alignment device 100. It isenvisioned that this orientation can be changed.

[0081]FIG. 20 illustrates another cutting guide 250 according to anotherembodiment of the present invention. The cutting guide 250 of thisparticular embodiment has a number of tibial pin guides 256 and a numberof femoral pin guides 258, similar to those defined in connection withprevious embodiment. In this particular embodiment, however, there arethree evenly spaced tibial pin guides 256 and two femoral pin guides258.

[0082] The cutting guide 250 has a mounting opening 260 for receiving acomplementary mounting post 261 on an alignment device. The mountingopening 260 has a rectilinear cross-section that is sized to closelyreceive the complementary mounting post 261. Because the mountingopening 260 and mounting post 261 are rectilinear, the cutting guide 250will not rotate over a substantial angle with respect to the alignmentdevice. Consequently, the practitioner can engage the cutting guide 250with an alignment device and avoid the task of aligning the cuttingguide with a patient's leg. The orientation of the mounting opening 260and/or the post 261 can vary.

[0083] The cutting guide has a femoral cutting groove 262 for cuttingthe distal end of the patient's femur. The femoral cutting groove 262 issubstantially the same as that described in connection with the previousembodiment.

[0084] The cutting guide 250 also has four tibial cutting grooves264/266/268/270. The four tibial cutting grooves 264/266/268/270 arespaced apart to provide the practitioner with a number of options formaking the horizonal tibial cut. For example, the tibial cutting groovescan be spaced 8, 10, 12 and 14 millimeters from the distal end of thefemur, respectively.

[0085] FIGS. 21-24 illustrate a low profile cutting/drilling guide 170for use in making the cuts and drilling the holes in the distal femurnecessary for the femur to receive the trial femoral implant 200 or acurrently standard femoral prosthesis. The cutting/drilling guide 170has a distal portion 172 that aligns with the posterior portion of thecondyle being operated upon; a proximal portion 174 opposite the distalportion; and a lower surface 176 shaped to generally mate with thecontour of the condyle after the horizontal femoral cut has been made.

[0086] The cutting/drilling guide 170 has a bevel cut guide 178 alignedto guide the practitioner in making the superior posterior chamfer cut;and a posterior cut guide 180 aligned to assist the practitioner inmaking the posterior articulating surface cut. The cutting/drillingguide 170 also has a pair of mounting hole guides 182 aligned to assistthe practitioner in drilling the mounting holes for the femoral implant.The bevel cut guide 178, the posterior cut guide 180 and the mountinghole guides 182 are generally sized and oriented to mount both thecurrently standard femoral prosthesis and the trial femoral implant 200discussed below. The spacing, alignment and/or size of each of thecutting and drilling guides, however, can be modified to accommodate anysimilar implant currently being marketed or developed in the future.

[0087] The cutting/drilling guide 170 also has a number of pinholes 184sized and aligned to direct either surgical pins or fixation screws intothe distal femur to retain the guide during the cutting and drillingportions of the procedure. In the illustrated embodiment, the pinholes184 are located within the boundary of the cutting/drilling guide 170.The particular placement and size of the pinholes 184 on thecutting/drilling guide 170 can vary based on whether the procedure willbe performed on the medial or lateral condyle, or based on practitionerpreference or other factors. In the illustrated embodiment, two pinholes184 are located near the distal portion 172 to align with the posteriordistal femur, and one pinhole 184 is located near the proximal portion174.

[0088] A threaded opening 186 is cetnrally located between the proximaland distal portions 174/172 of the cutting/drilling guide 170. Thethreaded opening 186 is sized and configured to mate with a threadedmounting instrument 300 (FIG. 27) to assist the practitioner in placingthe cutting/drilling guide 170 in the desired location, and in retainingthe guide firmly against the femur while it is being fixed thereto. Thethreaded opening 186 can be in a different location or alignment on thecutting/drilling guide 170, can have different shapes or sizes, or canuse different fasteners generally suitable for its described function.After the practitioner has placed the cutting/drilling guide 170 againstthe distal femur and has removed the threaded mounting instrument 300,the practitioner can peer through the threaded opening 186 to confirmthat the guide is properly seated on the distal femur.

[0089] As best illustrated in FIG. 22, the thickness of thecutting/drilling guide 170 is substantially reduced as compared tocutting and/or drilling guides of the prior art. In the illustratedembodiment, the thickness of the cutting/drilling guide 170 is nogreater than 15 mm, and preferably 1 cm. The distal portion 172 of theguide is even further reduced in thickness to allow the leg to beextended while the guide is mounted on the leg to allow the practitionerto confirm that the guide is mounted properly. In the illustratedembodiment, the thickness of the distal portion (i.e., the portiondistally located with respect to the posterior cut guide 180) is nogreater than 1 cm, and is preferably no greater than 5 mm. In someembodiments, it is envisioned that the thickness of the distal portion172 can be no greater than 1-1.5 mm.

[0090] The proximal portion 174 of the guide 170 has two opposingtapered surfaces 183, each extending laterally from the mounting guidehole 182. The tapered surfaces 183 are substantially reduced inthickness and tapered to provide room for the patella during theprocedure.

[0091] The cutting/drilling guide 170 of the present invention may havea number of advantages over instruments of the prior art. For example,the reduced thickness and contoured shape of the guide allows thepractitioner to perform this portion of the procedure through anincision considerably smaller than required by prior art methods andinstrumentation. These features also provide the practitioner with anunobstructed view of the distal femur to confirm that the guide isproperly seated before making the cuts and drilling the holes.

[0092] Unlike prior art cutting and drilling guides, which are commonlydesigned for full arthrotomy, the cutting/drilling guide 170 of thepresent invention allows the practitioner to perform this portion of theprocedure without dislocating the kneecap. The low profile and contourof the cutting/drilling guide 170 may also allow the practitioner tobetter view the procedure and to range the knee with the block in placeto verify appropriate block fixation.

[0093]FIGS. 25 and 26 illustrate a trial femoral implant 200 accordingto one particular embodiment of the present invention. The trial femoralimplant 200 has a smooth, curving outer surface 202 designed to engage acomplementary tibial implant (not shown). The outer surface 202 extendsbetween a distal end 204 that aligns with the posterior face of thecondyle being replaced, and a proximal end 206 that aligns with theanterior portion of the condyle. Opposite the outer surface 202, thetrial femoral implant 200 has a proximal inner surface 208 that mateswith the surface created by the horizontal femoral cut; a central innersurface 210 that mates with the femoral surface created by the superiorposterior chamfer cut; and a distal inner surface 212 that mates withthe femoral surface created by the posterior articulating surface cut.The trial femoral implant 200 also has a pair of mounting projections214 that engage the mounting holes in the distal femur that are drilledusing the mounting hole guides 182 in the cutting/drilling guide 170(FIG. 22).

[0094] A threaded hole 216 is bored through a central portion of thefemoral implant 200 between the outer surface 202 and the central andproximal inner surfaces 208/210. The threaded hole 216 is sized andthreaded to engage the threaded mounting instrument 300 that engages thecutting/drilling guide 170 (FIG. 27). The threaded hole 216 is alignedto allow the practitioner to engage the trial femoral implant 200 withthe prepared distal femur, and to urge the implant against the femurduring the implant process. Once the trial femoral implant 200 has beenfixed to the femur, the threaded mounting instrument 300 can be removedfrom the implant by unthreading the instrument and, thus, withoutpulling the implant away from the bone. The size, orientation, threadgage and pitch, and placement of the threaded hole 216 can varydepending on the particular condyle to which the trial femoral implant200 will be attached, or based on practitioner preferences or otherfactors.

[0095]FIG. 27 illustrates a mounting instrument 300 according to oneparticular embodiment of the present invention. The mounting instrument300 can be used to mount the cutting/drilling guide 170 and/or the trialfemoral implant 200 of the present invention. The mounting instrument300 incorporates a driving member 302 and a handle 304. The drivingmember 302 is an elongated, cylindrical member, and has a shaft 306projecting therefrom, which terminates at a threaded end 308. The shaft306 extends through the handle 304 and can rotate with respect to thehandle during use. As further illustrated in FIG. 28, the shaft 306 hasan annular groove 310 cut into its outer surface at a locationapproximately ¾ inch from the shaft's proximal end.

[0096]FIG. 29 illustrates a bearing 312 and a circlip 314 that togetherallow the handle 304 to rotate smoothly with respect to the drivingmember 302 while preventing the handle from slipping off the shaft 306.The bearing 312 has a bore 316 extending therethrough. The bore 316 hasa diameter approximately equal to the diameter of the shaft 306. Thecirclip 314 has a reduced diameter bore 318 therethrough for engagementwith the annular groove 310 in the shaft 306. With the bearing 312 slidonto the shaft 306 beyond the annular groove 310, the circlip 314 can beattached to the shaft 306 to retain the bearing on the shaft.

[0097]FIG. 30 further illustrates the handle 304 of the mountinginstrument 300. The handle 304 has an elongated, tubular channel 320extending substantially its entire length. The channel 320 has adiameter slightly larger than that of the shaft 306 to allow the shaftto freely rotate within the channel. One end of the handle 304 has anincreased diameter bore 322 extending approximately ¾ inch into the endof the handle. The diameter of the increased diameter bore 322 is sizedand shaped to complement the shape of the bearig 312 such that thebearing can be received within the increased diameter bore. A set screw324 can be threaded into a set screw opening 326 in the handle 304. Theset screw opening 326 is positioned to cause the set screw 324 toimpinge upon the bearing 312 when the bearing is fully inserted into theincreased diameter bore 322. As a result, when the bearing 312 is fullyengaged with the shaft 306, the circlip 314 is engaged with the annulargroove 310, the handle 304 is fully engaged with the bearing 312, andthe set screw 324 is fully engaged with the set screw opening 326, themounting instrument is operable such that the driving member 302 canrotate with respect to the handle 304 but the handle 304 cannot slideoff of the shaft.

[0098] Embodiments of the mounting instrument 300 have numerousadvantages over the prior art. For example, the mounting instrument 300can be engaged with a cutting/drilling guide 170 or a trial femoralimplant 200 to assist the practitioner in orienting the guide orprosthesis, urging it against the distal femur, and retaining it inposition during portions of the procedure. The practitioner can urge thehandle 304 toward the distal femur to maintain the guide or prosthesisagainst the distal femur, while simultaneously rotating the drivingmember 302 to remove the threaded end 308 of the shaft 306 from theguide or prosthesis. This may allow the practitioner to remove themounting instrument 300 from the guide or prosthesis without exerting atensile force on the guide or prosthesis, reducing the likelihood thatthe guide or prosthesis will be prematurely moved or removed from thedistal femur.

[0099]FIGS. 31 and 32 illustrate a pin driver 340 according to oneparticular embodiment of the present invention. The pin driver 340incorporates the handle 342 and an elongated shaft 344 projecting fromone end of the handle. At the end of the shaft 344 opposite the handle342, a hollow 346 is formed extending into the shaft 344 a portion ofthe distance toward the handle 342. In the illustrated embodiment, thehollow 346 extends approximately ½ inch into the shaft 344 andterminates at a substantially flat bottom surface 348. The illustratedhollow 346 has a circular cross-section that is slightly larger indiameter than a standard surgical pin. Accordingly, the head of asurgical pin can be inserted into the hollow 346 until me pin contactsthe bottom surface 348. The end of the handle 342 opposite the shaft 344is flat to allow the pin driver 340 to be struck by a hammer or similartool to drive the surgical pin into the bone.

[0100]FIGS. 33 and 34 illustrate a nut driver 350 according to oneparticular embodiment of the present invention. The nut driver has anelongated handle 352 attached to an elongated shaft 354 that projectsfrom the handle. The handle 352 can have a cylindrical shape, can besmooth, rough or otherwise finished to improve grip, or can be shapedsimilar to a traditional screwdriver. The shaft 354 in the illustratedembodiment is shaped to engage a nut or other fastener having an Allenhead. The shaft 354, however, can have a wide variety of shapes forengagement with a wide variety of nuts or other fasteners.

[0101]FIGS. 35 through 40 illustrate a method for creating a desiredalignment in a knee, and for making the horizontal, tibial and femoralcuts of a knee replacement procedure, according to one particularembodiment of the present invention. FIG. 35 shows portions of a femur400 and a tibia 402 from a leg 404 prior to the method of the presentinvention. A distal femur 406 abuts a proximal tibia 408, the distalfemur terminating in a pair of condyles 410 which contact a tibialplateau 412 at the extreme proximal tibia 408. The method described inthis particular embodiment of the present invention is applicable toboth the medial and a lateral condyle and, accordingly, the illustratedleg can be the patient's left or right leg. The condyle 410 located onthe left side of the illustration in FIG. 35 has a portion of diseasedbone 414. The primary purpose of the procedure of this embodiment of thepresent invention is to remove the diseased bone 414 from the condyle410, and to replace the removed bone with a femoral prosthesis. As partof this procedure, a portion of the tibial plateau 412 will also beremoved to provide a surface and space for a tibial prosthesis thatengages the femoral prosthesis.

[0102]FIG. 36 illustrates the distal femur 406 and the proximal tibia408 after the tibial plateau 412 has been prepared for this particularmethod of the present invention. A portion of the tibial plateau 412 onthe side with the diseased bone 414 on the distal femur 406 has been cutaway to provide a flat surface 416. The flat surface 416 can be madeusing a standard surgical saw 418. The practitioner can make aconservative cut in the proximal tibia 408 to create the flat surface416, but which removes less bone than necessary for even the thinnesttibial prosthesis. This cut provides a flat surface to receive thealignment device or the spacer. Accordingly, the practitioner may not beat risk for removing more bone than necessary.

[0103] After the flat surface 416 has been created, the practitioner caninsert an alignment device or spacer, such as the one described above,between the distal femur 406 and the proximal tibia 408. As illustratedin FIG. 37, an alignment device 100 has been slid between the condyle410 on the distal femur 406 and the flat surface 416 on the proximaltibia 408. In the illustrated configuration, the alignment device 100 isin the closed position such that the distance between the lower surface120 of the prong 108 and the top surface 130 of the leg 112 is at theminimum thickness “t” (note: the alignment device 100 is inverted inFIGS. 37-40 compared to that shown in FIG. 1). Because of the bone andcartilage loss associated with the presenting disease and the minimalbone removed to create the flat surface, a tibial axis 420 extendingalong a length of the tibia 402 is out of alignment with respect to afemoral axis 422 extending along the length of the femur 400. To correctthe alignment of the tibial and femoral axes 420/422, the practitionercan rotate the screw 124 to space the second member 104 of the alignmentdevice 100 apart from the first member 102 (as illustrated in FIG. 10).

[0104]FIG. 38 illustrates the leg 404 after the practitioner hasmanipulated the alignment device 100 to align the tibial axis 420 withthe femoral axis 422. To achieve this configuration, the alignmentdevice 100 is spread apart until the lower surface 120 is spaced apartfrom the top surface 130 by the increased thickness “T.” As thepractitioner manipulates the alignment device 100 to move the tibia 402between the alignment illustrated in FIG. 37 and that illustrated inFIG. 38, the alignment device urges the tibia apart from the femur 400.The alignment can then be adjusted to practitioner preference, which maynot always result in the tibial axis 420 being exactly colinear with thefemoral axis 422. An alignment rod 424 can be connected by an alignmentblock 426 to the post 110 on the alignment device 100. The practitionercan use the alignment rod 424 to visually confirm that the leg 404 is inthe desired alignment. Once the tibia 402 is in the desired alignment,the practitioner can remove the alignment rod 424 and alignment block426 from the post 100.

[0105]FIGS. 39 and 40 illustrate the next step in this particular methodof the present invention. After the alignment rod and alignment block424/426 are removed from the post 11O of the alignment device 100, thecutting guide 150 can be installed on the post. The mounting opening 160(FIG. 16) on the cutting guide 150 is slid over the post 110 of thealignment device 100 until the cutting guide 150 contacts the centralbody 106 of the first member 102 and/or the base 114 of the secondmember 104. The practitioner can rotate the cutting guide 150 about thepost 110 until the cutting guide is in the desired alignment (e.g.,perpendicular to the mechanical or weight-bearing axis of the tibia),and fix the cutting guide 150 to the distal femur 406 and proximal tibia408. Pins 428 can be inserted through the tibial pin guides 156 andfemoral pin guide 158, and driven using the pin driver 340 (FIG. 31)into the proximal tibia 408 and distal femur 406, respectively. With thepins 428 driven into the bones, the cutting guide 150 is maintained in afixed relationship with respect to both the distal femur 406 and theproximal tibia 408. The cutting guide 150 accordingly is in a fixedposition to guide the practitioner when making the horizontal, femoraland tibial cuts.

[0106] As best illustrated in FIG. 40, the femoral cutting groove 162 isaligned to direct the surgical saw 418 against the distal femur 406. Asdiscussed above in connection with FIG. 17, the horizontal femoral cut430 is approximately 3.5 millimeters from the extreme distal end of thedistal femur 406 to accommodate the femoral implant 200. The scaleillustrated in portions of FIGS. 37-42 has been distorted to bestillustrate the invention.

[0107] The first and second tibial cutting grooves 164/166 are alignedto guide the surgical saw 418 against the proximal tibia 408. Asdiscussed above in connection with FIG. 17, the first tibial cuttingguide 164 is located to place the horizontal tibial cut 432 eightmillimeters from the extreme distal end of the distal femur 406, and thesecond tibial cutting guide 166 is located to position the horizontaltibial cut ten millimeters from the extreme distal end of the distalfemur.

[0108] After the horizontal, tibial and femoral cuts have beencompleted, the pins 428 or other fasteners retaining the cutting guide150 to the distal femur 406 and proximal tibia 408 can be removed toseparate the cutting guide from the patient. The alignment device 100can then be slid from between the distal femur 406 and the proximaltibia 408. If necessary, the surgical saw 418 can be used to completeany cuts, or to separate any remaining bone from the newly cut area. Forexample, the practitioner may make a vertical cut at the central edge ofthe horizontal, tibial or femoral cut to separate a remaining portion ofbone.

[0109] At this point in the procedure, the distal femur 406 is preparedto be shaped for receiving a trial femoral implant 200. The mountinginstrument 300 can be engaged at its threaded end 308 with the threadedopening 186 on the cutting/drilling guide 170. With the lower surface176 of the cutting/drilling guide 170 urged against the surface of thedistal femur created by the horizontal femoral cut, the practitioner canattach the cutting/drilling guide to the femur by driving pins or usingscrews through the pinholes 184. Once the cutting/drilling guide 170 hasbeen fixed to the distal femur 406, the practitioner can rotate thehandle 304 of the mounting instrument 300 to remove the mountinginstrument from the cutting/drilling guide. The practitioner can use thesurgical saw 418 to make the superior posterior chamfer cut through thebevel cut guide 179 and the posterior articulating surface cut throughthe posterior cut guide 180, and can use a surgical drill to bore themounting holes in the distal femur using the mounting hole guides 182.These cuts and holes are configured for mounting the trial femoralimplant 200, which conforms with a currently standard femoralprosthesis; these cuts and holes can vary as the shape and configurationof femoral prostheses change between manufacturers and over time. Afterremoving the pins, the practitioner can separate the cutting/drillingguide 170 from the distal femur 406.

[0110] The tibial surface is then sized and prepared according to theguidelines for the specific prosthesis being utilized. The practitionermay then temporarily implant the trial prosthesis to confirm thealignment, stability and fit.

[0111] To mount the trial femoral implant 200 on the distal femur 406,the practitioner engages the threaded end 308 of the mounting instrument300 with the threaded hole 216 on the prosthesis. The practitioner thenprepares the prosthesis and/or distal femur 406 with adhesives or otherbonding agents and urges the femoral prosthesis against the distal femurusing the mounting instrument 300. It is impacted into place withstandard instruments.

[0112] The practitioner can then implant the tibial prosthesis. Becausethe practitioner selected the desired alignment in the leg prior tomaking the horizontal, tibial and femoral cuts, the practitioner canimplant the pre-selected tibial prosthesis knowing that the alignment inthe leg is likely to be the desired alignment. The practitioner canimplant the tibial prosthesis in the standard manner.

[0113] The method of the present invention has many advantages over themethods of the prior art. For example, the method of this particularembodiment of the present invention may allow the practitioner to selectthe desired ultimate alignment of the patient's leg prior to making thehorizontal tibial and horizontal femoral cuts. As a result, thepractitioner can make each of these cuts only once and obtain the properalignment between the tibia and the femur. The cuts are assured to beparallel, which can be important for long-term survival of the implant.This method thus may eliminate the requirement that the practitionermake multiple cuts to create the proper leg alignment.

[0114] The procedure of this embodiment of the present invention mayalso allow the practitioner to align the leg and make the horizontal,tibial and femoral cuts all through an incision that is significantlysmaller than those used in prior art procedures. As a result, the riskand recovery time may be reduced for the patient.

[0115] This method is performed without using intramedullary rods.Performing this procedure without intramedullary rods may also havebenefits to the patients.

[0116]FIGS. 41 and 42 illustrate another method of aligning a leg 404,and for aligning horizontal, tibial and femoral cuts according toanother embodiment of the present invention. In FIG. 41, the spacer 140has been inserted between the distal femur 406 and the flat surface 416on the proximal tibia 408. The spacer 140 illustrated in FIG. 41 is toothin to create a desired alignment in which the tibial axis 420 iscollinear with the femoral axis 422. Accordingly, the practitioner maychoose to replace the spacer 140 with a different spacer having agreater thickness.

[0117]FIG. 42 illustrates the leg 404 in which the spacer 140 a, havingan increased thickness “d2” has been inserted between the distal femur406 and the proximal tibia 408. As illustrated in FIG. 42, the distance“d2” is appropriate to create an alignment in which the tibial axis 420is collinear with the femoral axis 422. In this configuration, the leg404 is aligned for the practitioner to perform the horizontal, femoraland tibial cuts.

[0118]FIG. 42 also illustrates the cutting guide 250 according to thisalternate embodiment of the present invention. The rectangular mountingopening 260 has been engaged with the spacer 140 a in a fixedorientation with respect to the leg 404. The cutting guide 250 can nowbe fixed to the distal femur 406 and proximal tibia 408, and thehorizontal femoral cut 430 and horizontal tibial cut 432 (FIG. 40) canbe made.

[0119] Although the methods described above have been performed on a legwhere the proximal tibia has been cut prior to insertion of thealignment device or spacer, the method of the present invention can insome instances be performed without the preliminary tibial cut. In suchcases the alignment device or spacer would be inserted between thedistal femur and the tibial plateau, and adjusted to create the desiredalignment as discussed above.

[0120] The methods of the present invention can be performed on theopposite side of the leg or on both sides of a particular leg, as thesituation demands. Accordingly, it is not the inventor's desire tospecify that the invention is for the medial or lateral condyle of theleft or right leg, but is instead universally applicable.

[0121] FIGS. 43-46 illustrate a combined alignment device and cuttingguide 500 according to still another embodiment of the presentinvention. In general, the combined alignment device and cutting guide500 incorporates many of the features of the alignment device 100 andcutting guide 150 as described above in connection with priorembodiments of the present invention. The duplicative featuresaccordingly are not discussed in this portion of the disclosure, but areassumed to be clear based on the prior disclosure.

[0122]FIGS. 43 and 44 best illustrate the elements and features of thecombined alignment device and cutting guide 500 of this particularembodiment of the present invention. The combined alignment device andcutting guide 500 incorporates a first member 502, a second member 504and a cutting guide 550. A shaft 506 on the first member 502 engages amounting opening 560 on the cutting guide 550. A prong 508 on the firstmember 502 projects in a downward direction as illustrated in FIG. 43from the cutting guide 550. A pair of opposing rails 505 on the secondmember 504 are engaged with a complementary pair of grooves 509 in thecutting guide 550. In the configuration illustrated in FIG. 43, therails 505 of the second member 504 have been slid into the grooves 509in the cutting guide 550 to a point in which a pair of legs 512 on thesecond member are generally coplanar with the prong 508 on the firstmember 502. A screw 524 is engaged with a hole 522 in the second member504 and contacts a depression 511 in the cutting guide 550. Rotation ofthe screw in the clockwise direction within the threaded hole 522 causesthe screw to move through the second member 504 and into the depression511. Once the screw 524 contacts the depression 511, continued rotationof the screw in the clockwise direction causes the second member 504 tomove away from the cutting guide 550. As a result, rotation of the screw524 moves the legs 512 apart from the prong 508 in a similar manner tomanipulation of the alignment device 100 discussed above.

[0123]FIGS. 45 and 46 illustrate the combined alignment device andcutting guide 500 in two configurations. In FIG. 45, the screw 524 hasbeen threaded out of the second member 504 to allow the second member toalign with the first member 502. The prong 508 consequently ispositioned coplanar with the legs 512. This alignment results in aminimum thickness “t” between a lower surface 520 and a top surface 530,similar to that discussed above in connection with alignment device 100.

[0124] In FIG. 46, the screw 524 has been threaded into the secondmember 504 to move the second member apart from the first member 502. Asa result, the lower surface 520 is spaced apart from the top surface 530by an increased distance “T”. This increased distance “T” can be used bythe practitioner as discussed above to manipulate the spacing andalignment of the patient's leg. Once the leg is in the desiredalignment, the cutting guide 550 can be fixed to the patient's leg usingpins or screws, and the physician can make the horizontal, tibial andfemoral cuts as generally discussed above.

[0125] From the foregoing it will be appreciated that, although specificembodiments of the invention have been described herein for purposes ofillustration, various modifications may be made without deviating fromthe spirit and scope of the invention. Accordingly, the invention is notlimited except as by the appended claims.

1. An instrument for aligning a leg during a knee replacement procedure,the instrument comprising: a first member configured to contact a distalfemur and to exert a force on the distal femur in a first direction; anda second member configured to contact a proximal tibia and to exert aforce on the proximal tibia in a second direction substantially oppositethe first direction, the second member being movable in the seconddirection with respect to the first member to move the tibia relative tothe femur.
 2. The instrument of claim 1 wherein the first and secondmembers are elongated and extend at least substantially parallel to alongitudinal axis between proximal and distal ends, the distal end ofthe first member having a thickness that is sufficiently thin to bemanually, slidably inserted at a first location between the distal femurand the proximal tibia, the distal end of the second member having athickness that is sufficiently thin to be manually, slidably inserted ata second location between the distal femur and the proximal tibia, thesecond location being distinct from the first location, and furthercomprising: an actuator coupled to the first and second members, theactuator being controllable to move the second member with respect tothe first member in a lateral direction with respect to the longitudinalaxis, and to thereby move the tibia with respect to the femur; and anelongated shaft projecting from the proximal end of at least one of thefirst and second members, the shaft being engageable with an alignmentrod for assisting a practitioner in determining the alignment of theleg.
 3. The instrument of claim 1 wherein the first and second membersare sized and shaped to be slidably inserted between the distal femurand the proximal tibia.
 4. The instrument of claim 1 wherein the firstand second members are sized and shaped to be slidably inserted betweenone of the lateral and medial distal femur and a corresponding one ofthe lateral and medial proximal tibia.
 5. The instrument of claim 1wherein the first and second members are sized and shaped to be slidablyinserted between the distal femur and the proximal tibia, the firstmember has a first contact surface configured to contact one of thedistal femur and proximal tibia, and the second member has a secondcontact surface configured to contact the other of the distal femur andproximal tibia.
 6. The instrument of claim 1 wherein the first andsecond members are sized and shaped to be slidably inserted between thedistal femur and the proximal tibia, the first member has a firstcontact surface facing a first direction and configured to contact oneof the distal femur and proximal tibia, the second member has a secondcontact surface facing a second direction and configured to contact theother of the distal femur and proximal tibia, the second direction beingsubstantially opposite the first direction, and the second member beingmovable in the second direction with respect to the first member.
 7. Theinstrument of claim 1 wherein the first and second members are elongatedand extend at least substantially parallel to a longitudinal axisbetween proximal and distal ends, the distal end of the first memberhaving a thickness that is sufficiently thin to be manually, slidablyinserieu at a first location between the distal femur and the proximaltibia, the distal end of the second member having a thickness that issufficiently thin to be manually, slidably inserted at a second locationbetween the distal femur and the proximal tibia, the second locationbeing distinct from the first location, and further comprising anactuator coupled to the first and second members, the actuator beingcontrollable to move the second member with respect to the first memberin a lateral direction with respect to the longitudinal axis, and tothereby move the tibia with respect to the femur.
 8. The instrument ofclaim 1 wherein the first and second members are elongated and extend atleast substantially parallel to a longitudinal axis between proximal anddistal ends, the distal ends of the first and second members each havinga thickness that is sufficiently thin to be manually, slidably insertedbetween the distal femur and the proximal tibia, and further comprising:an actuator coupled to the first and second members, the actuator beingcontrollable to move the second member with respect to the first memberin a lateral direction with respect to the longitudinal axis, and tothereby move the tibia with respect to the femur.
 9. The instrument ofclaim 1 wherein the first and second members are elongated and extend atleast substantially parallel to a longitudinal axis between proximal anddistal ends, the distal ends of the first and second members each beingsized and shaped to be manually, slidably inserted between one of themedial and lateral sides of the distal femur and a corresponding one ofthe medial and lateral sides of the proximal tibia, and furthercomprising: an actuator coupled to the first and second members, theactuator being controllable to move the second member with respect tothe first member in a lateral direction with respect to the longitudinalaxis, and to thereby rotate the tibia with respect to the femur.
 10. Theinstrument of claim 1 wherein the first and second members are elongatedand extend at least substantially parallel to a longitudinal axisbetween proximal and distal ends, the distal ends of the first andsecond members each being sized and shaped to be mail-manually, slidablyinserted between one of the medial and lateral sides of the distal femurand a corresponding one of the medial and lateral sides of the proximaltibia, and further comprising: an actuator coupled to the first andsecond members, the actuator being controllable to move the secondmember with respect to the first member in a lateral direction withrespect to the longitudinal axis, and to thereby rotate the tibia withrespect to the femur; and an alignment rod coupled with at least one ofthe first and second members, the alignment rod being alignable in thelateral direction for assisting a practitioner in determining thealignment of the leg.
 11. A system for use during at least a portion ofa knee replacement procedure, the system comprising: a first memberconfigured to contact a distal femur and to exert a force on the distalfemur in a first direction; a second member configured to contact aproximal tibia and to exert a force on the proximal tibia in a seconddirection substantially opposite the first direction, the second memberbeing movable in the second direction with respect to the first membersuch that a practitioner can move the tibia relative to the femur into adesired alignment; an actuator coupled to the first and second members,the actuator being controllable to move the second member with respectto the first member and retain the second member in a desired position;and a cutting guide configured to be temporarily fixed to at least oneof the proximal tibia and distal femur, the cutting guide having atleast one opening therein sized and shaped to receive a surgical cuttingimplement, the opening being aligned to guide the cutting implement to aselected location in a selected alignment for cutting one of the distalfemur and proximal tibia.
 12. The system of claim 11 wherein the cuttingguide is coupled to at least one of the first and second members. 13.The system of claim 11 wherein the cutting guide is removably coupled toat least one of the first and second members.
 14. The system of claim11, further comprising an elongated shaft projecting from the proximalend of one of the first and second members, and wherein the cuttingguide is removably coupled to the shaft.
 15. The system of claim 11,further comprising: an elongated shaft projecting from the proximal endof one of the first and second members; and an alignment rod removablycoupleable to the shaft, and wherein the cutting guide is removablycoupleable to the shaft such that the alignment rod can be coupled tothe shaft to assist in aligning a patient's leg and the cutting guidecan be coupled to the shaft to assist in cutting at least one of thepatient's proximal tibia and distal femur.
 16. The system of claim 11wherein the distal ends of the first and second members are sized andshaped to be manually, slidably inserted between one of the medial andlateral sides of the distal femur and a corresponding one of the medialand lateral sides of the proximal tibia.
 17. The system of claim 11wherein the cutting guide comprises a plurality of holes for receiving acorresponding plurality of fasteners, the holes being aligned to directthe fasteners into the distal femur and proximal tibia to fix thecutting guide with respect to the distal femur and proximal tibia duringthe portion of the procedure.
 18. The system of claim 11 wherein thedistal ends of the first and second members are sized and shaped to bemanually, slidably inserted between one of the medial and lateral sidesof the distal femur and a corresponding one of the medial and lateralsides of the proximal tibia, and the cutting guide comprises a pluralityof holes for receiving a corresponding plurality of fasteners, the holesbeing aligned to direct the fasteners into the distal femur and proximaltibia to fix the distal femur and proximal tibia with respect to thecutting guide during the portion of the procedure.
 19. The system ofclaim 11 wherein the first and second members are sized and shaped to beslidably inserted between the distal femur and the proximal tibia. 20.The system of claim 11 wherein the cutting guide has a first opening anda second opening therethrough, the first opening being oriented on thecutting guide to align the cutting implement for making a horizontaltibial cut and the second opening being oriented on the cutting guide toalign the cutting implement for making a horizontal femoral cut.
 21. Thesystem of claim 11 wherein the cutting guide has a first opening and asecond opening therethrough, the first opening being oriented on thecutting guide to align the cutting implement for making a horizontaltibial cut and the second opening being oriented on the cutting guide toalign the cutting implement for making a horizontal femoral cut, thesecond opening being spaced from the first opening by a selecteddistance to provide a desired spacing for a prosthetic implant such thatthe knee with the prosthetic implant will be in the desired alignment.22. The system of claim 11 wherein the cutting guide has a first openingand a second opening therethrough, the first opening being oriented onthe cutting guide to align the cutting implement for making a horizontaltibial cut and the second opening being oriented on the cutting guide toalign the cutting implement for making a horizontal femoral cut, thesecond opening being spaced from the first opening by a variabledistance such that the practitioner can provide a desired spacing for aprosthetic implant and the knee with the prosthetic implant will be inthe desired alignment.
 23. A system for use during a portion of a kneereplacement procedure, the system comprising: a spacer being insertablebetween a distal femur and a proximal tibia to temporarily fix theproximal tibia in a selected position relative to the distal femurduring the portion of the procedure; and a cutting guide configured tobe temporarily fixed to at least one of the proximal tibia and distalfemur, the cutting guide having at least one opening therein sized andshaped to receive a surgical cutting implement, the opening beingaligned to guide the implement to a selected location in a selectedalignment for cutting one of the distal femur and proximal tibia. 24.The system of claim 23 wherein the cutting guide is coupled to thespacer.
 25. The system of claim 23 wherein the cutting guide isremovably coupled to the spacer.
 26. The system of claim 23, furthercomprising an elongated shaft projecting from the spacer, and whereinthe cutting guide is removably coupled to the shaft.
 27. The system ofclaim 23, further comprising: an elongated shaft projecting from thespacer; and an alignment rod removably coupleable to the shaft, andwherein the cutting guide is removably coupleable to the shaft such thatthe alignment rod can be coupled to the shaft to assist a practitionerin aligning a patient's leg, and the cutting guide can be coupled to theshaft to assist the practitioner in cutting at least one of thepatient's proximal tibia and distal femur.
 28. The system of claim 23wherein the cutting guide comprises a plurality of holes for receiving acorresponding plurality of fasteners, the holes being aligned to directthe fasteners into the distal femur and proximal tibia to fix thecutting guide with respect to the distal femur and proximal tibia duringthe portion of the procedure.
 29. The system of claim 23 wherein thespacer is sized and shaped to be manually, slidably inserted between oneof the medial and lateral sides of the distal femur and a correspondingone of the medial and lateral sides of the proximal tibia.
 30. Thesystem of claim 23, further comprising a plurality of spacers, eachspacer having a distinct thickness.
 31. The system of claim 23, furthercomprising a plurality of spacers, each spacer having a distinctthickness, and wherein each spacer is sized and shaped to be manually,slidably inserted between one of the medial and lateral sides of thedistal femur and a corresponding one of the medial and lateral sides ofthe proximal tibia, the spacers being selectable by a practitioner tocreate a desired alignment between the tibia and the femur.
 32. Thesystem of claim 23, further comprising: a plurality of spacers, eachspacer having a distinct thickness, and wherein each spacer is sized andshaped to be manually, slidably inserted between one of the medial andlateral sides of the distal femur and a corresponding one of the medialand lateral sides of the proximal tibia, the spacers being selectable bya practitioner to create a desired alignment between the tibia and thefemur; and an alignment rod coupleable with the spacers, the alignmentrod being alignable with at least one of the tibia and femur forassisting a practitioner in selecting the spacer that creates thedesired alignment.
 33. The system of claim 23, further comprising: aplurality of spacers, each spacer having a distinct thickness, andwherein each spacer is sized and shaped to be manually, slidablyinserted between one of the medial and lateral sides of the distal femurand a corresponding one of the medial and lateral sides of the proximaltibia, the spacers being selectable by a practitioner to create adesired alignment between the tibia and the femur; an elongated shaftprojecting from each of the spacers; and an alignment rod removablycoupleable to the shaft, and wherein the cutting guide is removablycoupleable to the shaft; whereby the alignment rod can be coupled to theselected shaft to assist a practitioner in selecting the proper spacerfor aligning a patient's leg, and the cutting guide can be coupled tothe shaft to assist the practitioner in cutting at least one of thepatient's proximal tibia and distal femur.
 34. The system of claim 23wherein the cutting guide has a first opening and a second openingtherethrough, the first opening being oriented on the cutting guide toalign the cutting implement for making a horizontal tibial cut and thesecond opening being oriented on the cutting guide to align the cuttingimplement for making a horizontal femoral cut.
 35. The system of claim23 wherein the cutting guide has a first opening and a second openingtherethrough, the first opening being oriented on the cutting guide toalign the cutting implement for making a horizontal tibial cut and thesecond opening being oriented on the cutting guide to align the cuttingimplement for making a horizontal femoral cut, the second opening beingspaced from the first opening by a selected distance to provide adesired spacing for a prosthetic implant such that the knee with theprosthetic implant will be in the desired alignment.
 36. The system ofclaim 23 wherein the cutting guide has a first opening and a secondopening therethrough, the first opening being oriented on the cuttingguide to align the cutting implement for making a horizontal femoral cutand the second opening being oriented on the cutting guide to align thecutting implement for making a horizontal tibial cut, the second openingbeing spaced from the first opening by a variable distance such that thepractitioner can provide a proper spacing for a prosthetic implant suchthat the knee with the prosthetic implant will be in the desiredalignment.
 37. A cutting guide for use during a knee replacementprocedure, the cutting guide comprising: a body configured to betemporarily fixed with respect to a proximal tibia and a distal femur,the body having at least first and second openings therethrough, thefirst and second openings each being sized and shaped to receive asurgical cutting implement, the first opening being aligned to guide thecutting implement for cutting the distal femur and the second openingbeing aligned to guide the cutting implement for cutting the proximaltibia.
 38. The cutting guide of claim 37 wherein the first opening isaligned to guide the cutting implement for making a horizontal femoralcut, and the second opening is aligned to guide the cutting implementfor making a horizontal tibial cut.
 39. The cutting guide of claim 37wherein the first opening is aligned to guide the cutting implement formaking a horizontal femoral cut, and the second opening is aligned toguide the cutting implement for making a horizontal tibial cut, andwherein the second opening is spaced apart from the first opening by adistance selected to provide a desired spacing for a prosthetic kneeimplant.
 40. The cutting guide of claim 37 wherein the first opening islocated in a first portion of the body and aligned to guide the cuttingimplement for making a horizontal femoral cut, and the second opening islocated in a second portion of the body and aligned to guide the cuttingimplement for making a horizontal tibial cut, and wherein the secondportion of the body is movable with respect to the first portion of thebody to adjust a distance between the first and second openings, thedistance being variable to provide a desired spacing for a prostheticimplant.
 41. The cutting guide of claim 37 wherein the body isconfigured to be fixed to at least one of the proximal tibia and thedistal femur.
 42. The cutting guide of claim 37 wherein the body isconfigured to be fixed to the proximal tibia and the distal femur. 43.The cutting guide of claim 37 wherein the body comprises a plurality ofapertures configured to receive a plurality of fasteners for fixing thebody of the cutting device to the proximal tibia and the distal femur.44. The cutting guide of claim 37 wherein the body comprises a pluralityof apertures configured to receive a plurality of fasteners for fixingthe proximal tibia and the distal femur with respect to the first andsecond openings.
 45. A prosthetic implant for a knee replacementprocedure, the implant comprising: a body having an inner surfaceconfigured to mate with a distal femur, an outer surface configured forsliding engagement with a tibial implant, and an opening extending fromthe outer surface at least partially toward the inner surface, theopening being configured to releasably, fixedly receive an instrumentfor carrying the implant and urging the implant against the distalfemur.
 46. The implant of claim 45 wherein the opening is centrallylocated with respect to the outer surface.
 47. The implant of claim 45wherein the opening in the body of the implant is threaded forengagement with a complementary, threaded portion of the instrument. 48.The implant of claim 45 wherein the opening extends entirely through thebody of the implant.
 49. The implant of claim 45 wherein the innersurface of the implant further comprises at least one protuberance forengagement with a mounting hole in the distal femur, and wherein aradial axis of the opening in the body of the implant is generallyaligned with the at least one protuberance.
 50. The implant of claim 45wherein the inner surface of the implant further comprises a pair ofprotuberances for engagement with a complementary pair of mounting holesin the distal femur, and wherein a radial axis of the opening in thebody is at least substantially parallel with and positioned between theprotuberances.
 51. The implant of claim 45 wherein the opening in thebody of the implant is threaded, and further comprising a mountinginstrument, the mounting instrument having a threaded portion removably,threadedly engaged with the opening in the body of the implant.
 52. Theimplant of claim 45 wherein the opening in the body of the implant isthreaded, and further comprising a mounting instrument having proximaland distal ends, the distal end of the mounting instrument having athreaded portion removably, threadedly engaged with the opening in thebody of the implant, the proximal end of the mounting instrument havinga first portion coupled to the threaded portion to rotate with thethreaded portion and a second portion rotatably coupled to the firstportion to freely rotate about the first portion such that an individualmounting the implant to the distal femur can urge the implant againstthe femur by exerting a force on the second portion, and cansimultaneously remove the mounting instrument from the implant byrotating the first portion.
 53. A template for assisting an individualin preparing a distal femur for receiving a femoral implant during aknee replacement procedure, the template comprising: a body having aproximal end, a distal end opposite the proximal end, a contact surface,and an outer surface facing away from the contact surface, the distalportion of the contact surface being curved to closely conform with aportion of the distal femur, the body having at least one attachmentopening sized and shaped to receive a fastener, the attachment openingbeing aligned to direct the fastener into the distal femur when thecontact surface of the body is conformed to the distal femur such thatthe fastener can retain the template to the distal femur, the outersurface near the proximal end of the body being sufficiently thin andshaped to closely conform with a posterior portion of the distal femursuch that the knee can be extended with the template affixed to thedistal femur, the body having at least one guide opening sized andshaped for receiving one of a drill bit and a saw blade, the guideopening being aligned to direct the one of a drill bit and a saw bladeinto the distal femur such that the distal femur can be prepared toreceive the femoral implant, a central portion of the body between theproximal end and the distal end being sufficiently thin and shaped tofit between the distal femur and a portion of a patella such that thebody can be affixed to the distal femur and the individual can performthe portion of the procedure without dislocating the patella.
 54. Thetemplate of claim 53 wherein the attachment portion is located near theproximal end of the body such that the fastener is directed into theposterior portion of the distal femur.
 55. The template of claim 53wherein the outer surface at the proximal portion of the body is curvedto conform with the curved portion of the contact surface.
 56. Thetemplate of claim 53 wherein the guide opening is sized and shaped todirect a saw blade into the distal femur to make a bevel cut in thedistal femur for mating with the implant.
 57. The template of claim 53wherein the at least one guide opening comprises two drill bit guidesand two saw blade guides, the drill bit guides being sized and shaped toreceive a drill bit and aligned to direct the drill bit into the distalfemur, and the saw blade guides being sized and shaped to receive a sawblade and aligned to direct the saw blade into the distal femur.
 58. Thetemplate of claim 53 wherein the central portion of the body is taperedtoward an edge of the body.
 59. The template of claim 53 furthercomprising opposing edges along the sides of the body between theproximal and distal ends, and wherein the central portion of the body istapered toward both opposing edges.
 60. The template of claim 53 whereinthe distal portion of the body has a thickness between the contactsurface and the outer surface, the thickness being no greater than fivemillimeters.
 61. The template of claim 53 wherein the distal portion ofthe body has a thickness between the contact surface and the outersurface, the thickness being no greater than three millimeters.
 62. Thetemplate of claim 53 wherein the distal portion of the body has athickness between the contact surface and the outer surface, thethickness being no greater than one millimeter.
 63. The template ofclaim 53 wherein the attachment opening is centrally located on thebody.
 64. The template of claim 53 wherein the body has a thicknessbetween the contact surface and the outer surface, the thickness beingno greater than fifteen millimeters.
 65. The template of claim 53wherein the body has a thickness between the contact surface and theouter surface, the thickness being no greater than ten millimeters.